Donor pretreatment with atorvastatin improves survival after major MHC mismatch BMT by reducing alloreactive T-cell expansion in vivo. (A) Balb/c mice were given 5 × 10⁶ TCD-BM cells and 1.2 × 10⁶ CD4⁺/CD8⁺ (4:1) T cells (both H-2K^q) after lethal irradiation with 800 cGy. Donor animals were fed with either PBS or AT with or without L-mevalonate by oral garvage for 10 days prior to transplantation. Survival of mice receiving TCD-BM (▵, n = 15), with T cells from donors treated with PBS (□, n = 15), atorvastatin 1 mg/kg (○, AT1, n = 15), atorvastatin 10 mg/kg (■, AT10, n = 15), AT1 plus L-mevalonate (◇, n = 10), AT10 plus L-mevalonate (●, n = 10). Percentage survival of Balb/c recipients is significantly higher when T cells are derived from donors treated with atorvastatin 1 mg/kg or 10 mg/kg as compared with PBS (○ versus □, P < .001; ■ versus □, P < .001). Survival data from 2 independent experiments including 8 and 7 recipients, respectively, are combined. (B) Expansion of luciferase-labeled T cells was quantified in emitted photons over total body area at serial time points after BMT. BLI signal intensity of mice receiving TCD-BM (▵, n = 15) with T cells from donors treated with PBS (□, n = 15), atorvastatin 1 mg/kg (○, AT1, n = 15), atorvastatin 10 mg/kg (■, AT10, n = 15), AT1 plus L-mevalonate (◇, n = 10), or AT10 plus L-mevalonate (●, n = 10). Signal intensity is significantly higher in animals receiving T cells from PBS-treated as compared with AT1- or AT10-treated animals (□ vs ○, P = .007; □ vs ■, P = .003). (C) Single time points depicting the expansion of luciferase transgenic (luc⁺) donor T cells in representative Balb/c mice receiving T cells from donors treated as indicated on top of each column for days 4, 8, and 12 after BMT. (D) Cytokine levels were measured in the supernatant of cocultures combining irradiated (30 Gy) APCs (Stimulator, H-2K^d) with T cells (Responder, H-2K^q) of each cell type, 2 × 10⁵ cells/well in flat-bottomed, 96-well plates derived from donors that were fed for 10 days with PBS or atorvastatin 10 mg/kg (AT) as indicated in the respective histogram (*P < .05). ELISA was performed as described in detail in “ELISA-based cytokine analysis.”